Otoacoustic Emissions in the Prediction of Sudden Sensorineural Hearing Loss Outcome

Abstract

To evaluate the role of otoacoustic emissions (OAEs) in the prediction of idiopathic sudden sensorineural hearing loss (ISSNHL) outcome. Open-label prospective study. Tertiary referral medical center. Fifteen ISSNHL patients (age: 57.6 ± 16.2 years) were prospectively followed 7 days, 14 days, and 3 months post-presentation and the commencement of treatment. Pure-tone audiometry, TEOAEs (Transient Evoked OAEs), and DPOAEs (Distortion Product OAEs) testing. The pure-tone threshold averages of the three most affected frequencies, detectability, and the signal-to-noise ratios (SNRs) values of the TEOAEs and DPOAEs were calculated. The main outcome measures were pure-tone hearing improvement, sensitivity, and specificity of the OAEs measures towards ISSNHL outcome. Patients having detectable TEOAEs on the first follow-up evaluation had average hearing improvement of 62 ± 41% whereas those with no response improved only by 11 ± 15% (P < 0.001). For the DPOAEs hearing improvement, results were 71 ± 37% and 10 ± 14%, respectively (P < 0.001). The sensitivity of recordable TEOAEs on the seventh day of follow-up towards the prediction of significant hearing improvement reached 71% and the specificity 100%. For the DPOAEs, the corresponding values were 83% and 100%. Univariate analysis showed significant contribution for the variance in hearing improvement by both TEOAEs and DPOAEs and their interaction (P values of 0.043, 0.005, and 0.009, respectively). The results suggest potential role of TEOAEs and DPOAEs evaluation in the early stage of treatment in the prediction of ISSNHL outcome.